Reporters were at the hospital to cover Deputy Defence Minister Thabang Makwetla's visit to soldiers wounded during a battle with rebels in the Central African Republic last weekend.

Hospital check-ins

Earlier this month, Mandela was admitted to a Pretoria hospital for a scheduled check-up. He was discharged the following day.

In December, Mandela underwent an operation to remove gallstones and to treat the recurring lung infection. He was discharged after an 18-day stay and placed under home-based high care at his Houghton, Johannesburg, residence.

In January, the presidency said Mandela had made a full recovery from the surgery and continued to improve.

In February 2012, he was admitted to hospital with a stomach ailment. At the time, the presidency said Mandela underwent a diagnostic procedure to investigate the cause of a long-standing abdominal complaint.

In January 2011, Mandela was taken to Milpark Hospital for routine tests relating to respiratory problems.

Mandela's last major public appearance was in July 2010, at the final of the Fifa World Cup at Soccer City stadium in Johannesburg.

Since then he has spent his time between Johannesburg and his ancestral village of Qunu in the Eastern Cape.

South Africa's first black president has a long history of lung problems, dating back to the time when he was a political prisoner on Robben Island during apartheid. While in jail he contracted tuberculosis.